ALTK-Evolve

IBM Research says ALTK-Evolve learned guidelines lift a GPT-4.1 customer-service agent above every retail entry on tau2-bench

Hugging Face Blog (IBM Research) published this on Oct 20, 2026 (source: huggingface.co).

IBM Research says ALTK-Evolve, which distills an agent's past successes and failures into short rules appended to its system prompt, took a basic GPT-4.1 ReAct agent to 67.5% Pass^4 on tau2-bench retail, above every retail entry in its October 12 leaderboard snapshot. IBM reports Pass^4 gains of 10 points in both retail (57.5 to 67.5) and airline (35.0 to 45.0), with no weight updates or human annotation. It says the guidelines raise input-token cost but slightly shorten conversations. These are IBM's own results.